EE. 
PP, 
GG. 
aa. Lip froma long-cuneate base obovate-rhombic to 
subquadrate-oblong, widest near apex 
ee ee eee eee eee 6. S. Fendleri alliance 
Lip as wide as or wider than long ........... E 
Lip with an incurved, filiform tooth in middle of ante- 
50) a Leg 4 | ea ee ae SECTION MONOSTACHYAE 
Lip either broadly apiculate or entire in front 
Teer Te kee Tee re ee ree SECTION ISOCHILAE 
a. Disc of lip with a longitudinal, fleshy, ridge-like 
callus in center .... 7. S. ascendens alliance 
aa. Disc of lip with a longitudinal groove in center 
peaxeeeneasse nee es 25 8. S. apiculata alliance 
Lip flat to concave, part of which with a longitudinal, 
somewhat imcrassate disc. ...4.4448e000%sae0%s G 
Lip deeply excavate, navicular to cymbiform 
avetae na ee rel Cee ees ae SECTION CHASMOSTELIS 
a. Secondary stem distinct for size of plant, elongate 
POT CC ee eee eT Lee Ty ee eee ey ee b 
aa. Secondary stem indistinct for size of plant, very 
short; lip linear-oblong, navicular, mostly hidden 
by a large plate .... 9. S. microchila alliance 
b. Lip triangular-hastate without a distinct basal 
DIME fois bhddadese tes 10. S. Porpax alliance 
bb. Lip ovate to elliptic or subglobose with a distinct 
transverse plate al Dase acs eieieed whines c 
c. Lip ovate to elliptic to subnavicular 
ee ere eee ee 11. S. despectans alliance 
cc. Lip subglobose-cymbiform 
eee Se ee Te Tee 12. S. angustifolia alliance 
Dorsal sepal much longer than lateral sepals 
eer eee eee Sere re ee SECTION LABIATAE 
a. Petals mucronate; plants caespitose, often proli- 
PeCOU. cose nee aha ees 13. S. triseta alliance 
aa Petals mucronate; plants caespitose, often prolif- 
CPOs. cise seeesya sees 13. S. triseta alliance 
Dorsal sepal hardly different from lateral sepals 
SECTION CONCAVE 
ee 
177 
